Implemented the 'any' operator

[zsxwing]

This implements the operator Any from #24 in all two variants.

However, I encountered two problems.

Updated: the online document http://msdn.microsoft.com/en-us/library/hh211993(v=vs.103).aspx is wrong. See my later discussion.

Another question is if I add the any method to rx.Observable<T>, some unit tests will fail as the method any in rx.Observable<T> overrides the method org.mockito.Matchers.any(java.lang.Class<T>) in some unit tests (e.g., rx.subjects.ReplaySubject<T>). Do I need to use another method name, or just modify the unit tests? Now the any methods in rx.Observable<T> are commented out.

Thanks.

[cloudbees-pull-request-builder]

RxJava-pull-requests #284 SUCCESS
This pull request looks good

[benjchristensen]

I haven't looked at the first question yet, but on the second one we'll likely need to stop importing org.mockito.Matchers.* and call it directly org.mockito.Matchers.any.

[zsxwing]

Sorry that I missed the keyword empty in my description. The first question is I'm not sure how to handle an empty observable sequence.

[cloudbees-pull-request-builder]

RxJava-pull-requests #285 ABORTED

[zsxwing]

I tested the C# Any today. The environment is VS2010 .Net 4.0.

I found the description in my VS is Determines whether any element of an observable sequence satisfies a condition. This is totally different from the online document http://msdn.microsoft.com/en-us/library/hh211993(v=vs.103).aspx.

I always did some tests for Any. Here is the code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reactive.Linq;
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var any = Observable.Empty().Any();
            any.Subscribe(
                x => Console.WriteLine("subscriber got " + x) // subscriber got False
            );
            any = Observable.Range(1, 5).Any();
            any.Subscribe(
                x => Console.WriteLine("subscriber got " + x) // subscriber got True
            );
            
            any = Observable.Empty().Any(
                x => true
            );
            any.Subscribe(
                x => Console.WriteLine("subscriber got " + x) // subscriber got False
            );
            any = Observable.Range(1, 5).Any(
                x => x > 3
            );
            any.Subscribe(
                x => Console.WriteLine("subscriber got " + x) // subscriber got True
            );
            any = Observable.Range(1, 5).Any(
                x => x > 5
            );
            any.Subscribe(
                x => Console.WriteLine("subscriber got " + x) // subscriber got False
            );
            Console.ReadLine();
        }
    }
}

Here is the output:

subscriber got False
subscriber got True
subscriber got False
subscriber got True
subscriber got False

In summary,

• If an observable sequence is empty, any emits false.
• If one element of an observable sequence satisfies the condition, any emits true.
• If all elements of an observable sequence do not satisfy the condition, any emits false.

[zsxwing]

I have implemented the correct 'any' operator. Please take a look. Thanks!

[cloudbees-pull-request-builder]

RxJava-pull-requests #286 ABORTED

[samuelgruetter]

In Scala, we will probably use isEmpty instead of any() (negated), and exists(somePredicate) instead of any(somePredicate). You could use these names also in Java, to avoid confusion and name conflicts.

[benjchristensen]

@zsxwing I don't have time tonight but will definitely get to this in the near future, thank you for getting involved!